Like many Americans, I was sad to hear about Senator John McCain’s recent cancer diagnosis. Though I don’t always agree with his political stances, I greatly admire many things about him, including his service during the Vietnam war.

Senator McCain has a type of malignant brain tumor called a glioblastoma multiforme (also called a GBM). This is the same sort of tumor that Ted Kennedy, Beau Biden, and Ethel Merman had. Since the news about the senator’s diagnosis came out, a lot has been written about the fact that GBMs are associated with a poor prognosis. This has made me think about the term “prognosis.” In my experience, patients and their families often misunderstand how doctors think about that term.

Prognosis is all about trying to answer the question, “What’s going to happen to this person?” It’s not always easy to tell. However, early in my training, my mentors taught me that all cancer patients can be divided into two groups, which they called “curative” and “palliative.”

If a patient was palliative, that meant that there was no real chance for curing their cancer. Treatments may still be helpful for slowing the cancer’s growth and reducing symptoms. But we knew from the beginning that the cancer would eventually cause the patient’s death.

Curative patients, on the other hand, had cancers that were potentially…well, curable. The goal of their treatment was to entirely eliminate their cancer. I often imagined those patients finishing their cancer therapy and going on to live long and healthy life. Eventually, I hoped, the cancer would just be a faded, bad memory in their past.

Even in cases where the goal is curative, there is still no guarantee that treatments will cure the cancer. Instead, treatments are intended to make it as likely as possible that the patient will be cured. Curative treatments are all about playing the odds. It’s like we’re at a casino in Las Vegas, and we’re trying to maximize our chances of winning at the blackjack table. With curative treatments, we’re doing everything we can to stack the deck in our favor.

Here’s another analogy: Imagine you’re out for a walk, and your goal is to cross a busy street. You could just step blindly out into traffic, but your risk of not making it to the other side would be high. There are some simple things you can take to make it more likely that you will make it across. You could:

Look to your left before you start to cross

Look to your right before you start to cross

Cross at a crosswalk

Wait for a walk signal from a traffic light

Doing any one of those alone would increase your odds of making it across the street alive. Doing two of them would improve your odds even more. Doing all four would give you the best shot. However, even if you do all four of them, your likelihood of making it still isn’t 100 percent. A speeding truck could come out of nowhere, or you could be hit by lightning, or you could have a heart attack when you’re halfway across. Also, even if you don’t do any of them, there’s still a chance you could, by pure luck, make it across the street alive. However, no one would ever recommend you try that!

Your cancer treatments are like these things you do to improve your likelihood of making it across the street. They are each intended to improve your chances of achieving a cure. They can’t make it absolutely certain you’ll be cured. What they do is shift the odds in your favor.

I’m sure Senator McCain’s doctors will do all that they can to stack the deck in his favor. Glioblastoma is usually treated with a combination of surgery, radiation, and chemotherapy. Though the odds aren’t great, a small minority of patients do achieve full cure, and go on to live years and years after their diagnosis. I certainly hope that for Senator McCain.

Andrew Howard, MD, is an Assistant Professor of Radiation & Cellular Oncology at the University of Chicago. He has written a new book for cancer patients and their families titled So You’ve Got Cancer: A Super Patient’s Guide to Diagnosis, Treatment, and Beyond. You can find it here.

2 Comments

In my non health profession world, it has come to my attention that diet as a form of cancer treatment is a very obscure idea. I noticed you mentioned the typical cancer treatments, “a combination of surgery, radiation, and chemotherapy” and couldn’t help but wonder. In your opinion, does a “diet-treatment” hold weight and if so, will it ever be taken serious in the mainstream medical world.
Thanks for the blog! It’s nice to see fresh thoughts (stumbled upon you through NPR) coming from a fellow Tulsa resident.
Sarah Thompson

Nutrition is crucial to maintaining health. In illness, its importance is heightened, because poor diet can exacerbate many conditions. Or be counterproductive to healing.

With malignant cancer, diet therapy is simply not enough to treat the condition, regardless of type. Think of diet as adjunct; wholly important, but the ‘right diet’ cannot in and of itself cure cancer.

At this stage of our medical/scientific knowledge, cancer treatment still relies on one or a combination of surgery, medication, and/or radiation.